The objective of this study was to evaluate the performances and microbial diversities for development of the effective hyperthermophilic digester system that consists of a hyperthermophilic reactor and hyperthermophilic or thermophilic reactor in series. Lab-scale reactors were operated continuously fed with artificial kitchen garbage. The effect of temperature on the acidification step was firstly investigated. Results indicated that 20.8% of COD solubilization was achieved at 70°C, with 12.6% at 80°C. The average protein solubilization reached 31% at 80°C. Methane conversion efficiency following the acidification was around 85% on average at 55°C, but decreased with increasing temperature and methane gas was not produced over 73°C. As well, bacteria affiliated with the methanogens dominated the population below 65°C, while those affiliated with acidogens were predominant over 73°C. These results indicated that the hyperthermophilic process has considerable benefits to treat wastewater or waste containing high concentration of protein.

You do not currently have access to this content.